% not sure about these colours!
\definecolor{c1}{HTML}{FF7F00}
\definecolor{c2}{HTML}{048BA8}
\definecolor{c3}{HTML}{16DB93}
\definecolor{c4}{HTML}{EFEA5A}
\definecolor{c5}{HTML}{F29E4C}
\definecolor{c6}{HTML}{256EFF}
\definecolor{c7}{HTML}{46237A}

\scalebox{1.35}{
\begin{forest}
rt/.style={draw=black,line width=1pt},
peer/.style={draw=black!60,edge={black!60,line width=0.7pt}},
peerleaf/.style={edge={black!60,line width=0.7pt}},
self/.style={draw=black,fill=black,edge={black,line width=1pt}},
selfpeer/.style={draw=black,line width=1pt,edge={black,line width=1pt}},
unused/.style={draw=black!20,edge={black!20,line width=0.7pt}},
[{},rt,for tree={circle,draw, l sep=20pt}
  [{},selfpeer,edge label={node[midway,left] {0}}
    [{},peer,edge label={node[midway,left] {0}}
      [{},peer,edge label={node[midway,left] {0}}
        [{},unused,edge label={node[midway,left] {0}}]
        [{},peerleaf,fill=c1,draw=c1,edge label={node[midway,right] {1}}]
      ]
      [{},peer,edge label={node[midway,right] {1}}
        [{},peerleaf,fill=c2,draw=c2,edge label={node[midway,left] {0}}]
        [{},unused,edge label={node[midway,right] {1}}]
      ]
    ]
    [{},selfpeer,edge label={node[midway,right] {1}} 
      [{},selfpeer,edge label={node[midway,left] {0}}
        [{},peerleaf,fill=c3,draw=c3,edge label={node[midway,left] {0}}]
        [{},self,edge label={node[midway,right] {1}}]
      ]
      [{},peer,edge label={node[midway,right] {1}}
        [{},peerleaf,fill=c4,draw=c4,edge label={node[midway,left] {0}}]
        [{},peerleaf,fill=c5,draw=c5,edge label={node[midway,right] {1}}]
      ]
    ] 
  ]
  [{},peer,edge label={node[midway,right] {1}}
    [{},unused,edge label={node[midway,left] {0}}
      [{},unused,edge label={node[midway,left] {0}}
        [{},unused,edge label={node[midway,left] {0}}]
        [{},unused,edge label={node[midway,right] {1}}]
      ]
      [{},unused,edge label={node[midway,right] {1}}
        [{},unused,edge label={node[midway,left] {0}}]
        [{},unused,edge label={node[midway,right] {1}}]
      ]
    ]
    [{},peer,edge label={node[midway,right] {1}} 
      [{},peer,edge label={node[midway,left] {0}}
        [{},fill=c6,peerleaf,draw=c6,edge label={node[midway,left] {0}}]
        [{},unused,edge label={node[midway,right] {1}}]
      ]
      [{},peer,edge label={node[midway,right] {1}}
        [{},fill=c7,peerleaf,draw=c7,edge label={node[midway,left] {0}}]
        [{},unused,edge label={node[midway,right] {1}}]
      ]
    ]
  ] 
]
\end{forest}
}